猪ERK6基因编码区的克隆及组织表达谱分析

利用RT-PCR方法扩增了猪ERK6基因编码区的序列，将扩增产物与pMD18-T载体连接，构建了重组质粒；重组质粒经PCR、酶切鉴定后进行测序；采用Northern杂交和半定量RT-PCR方法在猪不同部位骨骼肌中分析了ERK6基因转录本的个数、大小及组织表达谱。结果显示，所克隆的猪ERK6基因片段长1113bp，含有1个1104bp的开放阅读框（ORF），该ORF编码367个氨基酸；该基因与已报道的人ERK6基因核苷酸序列相似性为90％；猪ERK6基因在肌肉组织中只有一个转录本，大小约1．5kb。此基因在骨骼肌中的表达量最高，心、子宫次之，卵巢最低；而在脂肪、胃、肝、脾、肺、肾、十二指肠和胰腺中未见表达。结果表明，猪ERK6基因与已报道的小鼠和人ERK6基因一样，主要在骨骼中特异表达。     

TWO-DIMENSIONAL COLOR TISSUE DOPPLER IMAGING DETECTS MYOCARDIAL DYSFUNCTION BEFORE OCCURRENCE OF HYPERTROPHY IN A YOUNG MAINE COON CAT

A 20-month-old healthy male Maine Coon cat was referred for a cardiovascular evaluation. Physical examination and electrocardiogram were normal. The end-diastolic subaortic interventricular septal thickness (6 mm; reference range: < or = 6mm) and the mitral flow late diastolic velocity (0.89 m/s; reference range: 0.2-0.8m/s) were within the upper ranges. However, M-mode echocardiography did not reveal any sign of hypertrophic cardiomyopathy (HCM). Tissue Doppler imaging (TDI) identified a marked left ventricular free wall dysfunction characterized by decreased myocardial velocities in early diastole, increased myocardial velocities in late diastole and the presence of postsystolic contractions both at the base and the apex for the longitudinal motion. One year later, the diagnosis of HCM was confirmed by conventional echocardiography and the cat died suddenly 2 months later. This report demonstrates for the first time in spontaneous HCM the sensitivity of TDI for early diagnosis of myocardial dysfunction and suggests that TDI should form part of the screening techniques for early diagnosis of feline HCM.     

Mammary development and milk production in the sow: Effects of udder massage, genotype and feeding in late gestation

The primary aim of the study was to investigate whether post-ejection udder massage 1–2 weeks pp (post partum) had an effect on the amount of mammary tissue and milk production in the domestic sow.

The nursing behaviour of 35 primiparous LYL or YLY sows and their litters was followed on days 7 and 14 pp. The milk production was measured by the weigh–suckle–weigh method of the whole litter on days 11 and 18 pp. After weaning on day 28 pp, the sows were slaughtered and the mammary tissue excised and weighed.

No significant correlations were found between the duration of post-ejection udder massage and the subsequent milk production. LYL sows had more mammary tissue (P < 0.05) and their piglets spent more time performing post-ejection udder massage compared to the YLY sows (P < 0.01). Individual variation was found in the proportion of time that the sows were lying on either their right or left side. The weight of the mammary tissue from the left side was positively affected by the amount of udder massage (pre- and post-ejection massage) that the sows had received while lying on the right side relative to the amount that she had received while lying on the left side on day 7 pp (P < 0.01).

In conclusion, the intensity of udder massage influenced the amount of mammary tissue at slaughter. The genotype of the sow affected the expression of nursing behaviour and milk production. No connection was found between post-ejection udder massage and the measures of milk production 1–2 weeks pp. Finally, feeding during the last half of gestation affected the nursing behaviour.     

Tissue-specific antioxidative and neurotoxic responses to diazinon in Oreochromis niloticus

The purpose of this study was to evaluate oxidative stress and neurotoxic potential of organophosphorus (OP) insecticide diazinon in the sentinel freshwater fish, Oreochromis niloticus. Antioxidant and acetylcholinesterase (AChE) enzyme activities and malondialdehyde (MDA) and protein levels were measured spectrophotometrically in gill, kidney, alimentary tract, and muscle tissues of fish treated with sub-lethal diazinon concentrations for 1, 7, 15, and 30 days. Dose-dependent inhibitions of AChE were observed in all the experimental fish. On the contrary of alimentary tract, MDA levels were elevated in kidney and muscle and gill was not affected. AChE and MDA levels intercorrelated in kidney and muscle tissues. Diazinon had increased superoxide dismutase (SOD) activities in all the tissues, while kidney was the most affected tissue. Tissue-specific alterations were observed on catalase (CAT) and glutathione peroxidase (GPx) activities; however, the activities were not changed in gill and muscle tissues for GPx and in gill, muscle, and kidney tissues for CAT. Protein levels decreased in kidney, muscle, and alimentary tract, while increased in gill and alimentary tract in 15 days. With respect to these results, diazinon has oxidative and neurotoxic potentials in O. niloticus. Observed changes with diazinon treatment were generally tissue-specific and dose-dependent.     

不同饲养环境合作猪脂肪组织生脂基因 mRNA表达水平的比较研究

合作猪是生长在高寒草原以放牧为主的珍稀高原型猪种,为了探讨其品种特性的分子机制,分析测定了原产地合作猪及长期在不同环境和饲养条件下异地饲养合作猪脂肪组织脂肪生成的关键酶脂肪合成酶(FAS)、乙酰辅酶A羧化酶(ACC)1和转录因子固醇调控元件结合蛋白(SREBP)-1c、碳水化合物调控元件结合蛋白(ChREBP)mRNA表达水平,并与杜×大×长三元杂交猪进行了对比。试验结果发现,合作猪脂肪组织FAS、ACC1及ChREBP mRNA水平显著低于三元杂交猪(P<0.05),在长期异地饲养后,这些基因mRNA表达水平提高(P<0.05),而SREBP-1c mRNA表达水平在3个群体中没有明显变化(P>0.05)。结果提示,合作猪由于对低能量、低碳水化合物粗饲的长期适应,表现出脂肪组织生脂基因表达水平较低的生理学特性。     

微粒蒙脱石对猪组织铅水平、红细胞生成和肝脏ALA-D酶活性及铅诱导的脂质过氧化的影响

选60头体质量约33kg的“杜长大”杂交猪，随机分成2组，每组3个重复，一组饲以基础日粮＋10mg/kg铅＋0.5％微粒蒙脱石，另一组饲以基础日粮＋10mg／kg铅作为对照。研究结果表明：添加微粒蒙脱石组与对照组相比，明显降低了猪全血、脑、肝、肾、骨和毛等组织中铅含量：通过血细胞计数、血红素和血球容积测定表明，添加微粒蒙脱石组的红细胞生成显著增高，且肝脏中ALA—D酶活性显著提高。铅对肝脏的损伤作用明显。表现为丙二醛（MDA）含量显著升高（17．08％），过氧化氢酶（CAT）、超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GPx）含量分别降低85．73％、52．17％、47．56％，而在日粮中添加微粒蒙脱石可以显著改善铅诱导的上述损伤。结果提示，微粒蒙脱石对铅中毒有潜在的治疗作用。     

早熟禾品种耐寒变异植株无性系的建立

对草地早熟禾的小矮人品种耐寒变异植株无性系的建立进行了研究,并成功地诱导出小矮人嫩叶的愈伤组织,分化出丛生不定芽.诱导愈伤组织的理想培养基是MS BA 0.1mg/L 2,4-D 1 mg/L;由愈伤组织分化出苗的理想培养基是1/2 MS BA 0.1 mg/L 2,4-D 0.1 mg/L;试管苗极易移栽成活,耐寒变异性状保持不变.     

Effects of uremic serum of different molecular weight groups ongene and protein expression of connective tissue growth factor gene and proteinexpression in human renal tubular epithelial cells

AIM:To investigate the effects of uremic serum of different molecular weight groups on gene and protein expression of connective tissue growth factor (CTGF) in human renal tubular epithelial cells.METHODS:The serum from 40 chronic renal failure patients and 20 healthy volunteers were collected and uremic serum was segregated to three groups: >10 000 D,5 000-10 000 D,<5 000 D by 10 000 D and 5 000 D molecular weight Centricon Plus 20 Centrifugal Filter Devices.The protein expression of CTGF was examined by Western blotting.The mRNA expression of CTGF was detected by RT-PCR.RESULTS:CTGF gene expression were increased in 2.5%-20% uremic serum groups compared with that in normal control group,and it was the highest in 10% uremic serum groups.CTGF gene expression was increased significantly in molecular weight >10 000 D and 5 000-10 000 D groups,and the highest was in >10 000 D group,but it was no significant difference in <5 000 D group compared with that in normal control group.CTGF protein was increased in different molecular weight uremic serum groups compared with that in normal control group,and gradually increased following the increasing of uremic serum concentration and it was the highest in molecular weight >10 000 D group.CONCLUSION:Human renal tubulointerstitial fibrosis was accelerated significantly by uremic toxin,especially molecular weight >10 000 D uremic toxin through promoting the gene and protein expression of CTGF in renal tubular epithelial cells in patients with chronic renal failure.